中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
太阳暗条长期活动的统计特征研究

文献类型:学位论文

作者孔德芳
学位类别博士
答辩日期2014-05-26
授予单位中国科学院研究生院(云南天文台)
授予地点北京
导师李可军
关键词太阳活动 日珥(暗条) 耀斑 日冕物质抛射(CMEs)
其他题名Research on the statistical characteristics of solar filament long-term activity
学位专业天体物理
中文摘要太阳是离地球最近的一颗恒星,也是宇宙中唯一可以进行高分辨率成像观测和研究的恒星。它是地球上一切生命所需光和热的唯一来源,维持着人类生存和地球上一切生命活动所必需的适当环境。因此,太阳活动及其规律的研究对日地关系的研究、服务以及某些自然灾害的研究和预防都是非常重要的。本文首先对暗条的背景知识及暗条长期活动规律的研究现状进行简要的综述,然后详细介绍了我们在暗条长期活动的统计特征方面的研究工作,主要结果如下: 1、运用法国巴黎墨东天文台1919年3月至1989年12月的暗条观测资料,采用交叉相关分析和小波分析的方法研究了高纬度暗条的极向漂移。通过连续小波变换得到太阳活动周的长度是纬度的函数,并且表现出明显的11年周期。全局功率谱表明纬度50?以上和纬度60?以上太阳暗条的显著周期分别是10.77年和10.62年。交叉相关分析的结果表明纬度50?以上的太阳暗条领先纬度60?以上的太阳暗条6个月,在第16-21周的各个太阳活动周内,两组暗条数据也表现出不一样的相位关系。交叉小波分析也表明,在整个时间段上,纬度50?以上的太阳暗条领先于纬度60?以上的太阳暗条。此外,我们讨论了两组暗条数据的相位差和太阳活动强度之间的关系,并且粗略估计了极向漂移的速度。 2、运用法国巴黎墨东天文台的暗条观测资料(卡林顿自转周第876-1823周,对应于1919年3月至1989年12月),采用交叉相关分析和小波分析的方法研究了高低纬度太阳活动的领先问题。交叉相关分析表明高纬度暗条领先低纬度暗条12个卡林顿自转周。交叉小波变换和调和小波均表明高纬度暗条领先于低纬度暗条。统计检验的结果显示低纬度暗条与前一周的高纬度暗条关联性更强(比和后一周的高纬度暗条),并且具有显著的统计意义。研究表明,极区的高纬度暗条确实和后一周的低纬度暗条关联性更强,即高纬度太阳活动在相位上领先低纬度太阳活动。 3、运用1998年2月至2008年11月每天的暗条数据,分别讨论了高纬度和低纬度的南北半球不对称性。结果表明,对于低纬度来说,北半球占优;然而,高纬度的情况并非如此。因而,高纬度的半球不对称性应该和低纬度的半球不对称性无关。得到的结果支持了高纬度的磁场包含两部分的论点:一部分源于太阳内部的磁场浮现,另一部分源于低纬度弱磁场的极向漂移。 4、运用太阳动力学天文台(Solar Dynamics Observatory,简称SDO)的观测资料,研究了2012年4月19日位于太阳东南边缘两个连续爆发的暗条。第一个暗条(F1)爆发的初始阶段,F1的一只腿向第二个暗条(F2)移动并扫过F2。两个暗条之间发生了相互作用。F1爆发后,SOHO/LASCO观测到了一个CME,形成了一个双带耀斑和两个暗区(dimmings)。F1爆发时,F1上方的大尺度冕环被推向太阳的东南部,并且F2上方的大尺度冕环开始向东南方向打开。随后,F2开始变得不稳定并开始爆发。F2爆发后,形成了一个双带耀斑和一个CME。这些观测表明两个暗条的相互作用和F1爆发所引起的大尺度冕环的打开是导致F2爆发的最主要因素。
英文摘要The Sun is the nearest star to our earth, the only one high-resolution imaging observed and studied in the universe. It is the only source of light and heat indispensable for all life on the earth, maintaining a proper environment required for human existence and all life activities on the earth. Therefore, the study on solar activity and its varying pattern is very important for the research and service on the Sun-Earth relations, the research and prevention of some natural disasters. Firstly, the filament background knowledge and the research status of filament long-term activity patterns are introduced briefly. Then the statistical characteristic analysis of filament long-term activity is presented in detail. The main results are as follows: 1. In order to better understand the behavior of “rush to the poles”, we used the cross-correlation analysis and the wavelet transform methods to investigate the periodic characteristics and the phase relationship of two groups of solar filaments at high latitudes observed from March 1919 to December 1989. The length of the solar cycle derived from the continuous wavelet transform is a function of latitude, but still shows a significant 11-year cycle. The most significant periods of the solar filaments, respectively at higher latitudes than 50? and 60?, are 10.77 and 10.62 years by using the wavelet transform method. The solar filaments at higher latitudes than 50? have a time lead of six months with respect to the ones at higher latitudes than 60? from the cross-correlation analysis. Different solar cycles exhibited different phase relationship between two parts of solar filaments. The analysis of the cross-wavelet transform also indicates that the solar filaments at higher latitudes than 50? lead the ones at higher latitudes than 60? in the entire time interval. The relationship between the phase difference of two groups of solar filaments and the intensity of solar activity is also discussed. What’s more, the poleward shifting speeds are estimated. 2. Cross-correlation analysis and wavelet transform methods are used to investigate whether high-latitude solar activity leads low-latitude solar activity in time phase or not, using the data of the Carte Synoptique solar filaments archive from Carrington solar rotations (CRs) 876 to 1823. From the cross-correlation analysis, high-latitude solar filaments have a time lead of 12 CRs with respect to low-latitude ones. Both the cross-wavelet transform and wavelet coherence indicate that high-latitude solar filaments lead low-latitude ones in time phase. Furthermore, low-latitude solar activity is better correlated with high-latitude solar activity of the previous cycle than with that of the following cycle, which is statistically significant. Thus, the results confirm that high-latitude solar activity in the polar regions is indeed better correlated with low-latitude solar activity of the following cycle than with that of the previous cycle, namely, leading in time phase. 3. In the present study, we investigate the north-south asymmetry of solar filaments at low (< 50?) and high (>60?) latitudes, respectively, using daily filament numbers from January 1998 to November 2008 (solar cycle 23). We found that the northern hemisphere is dominant at low latitudes for cycle 23. However, a similar asymmetry does not occur for solar filaments at high latitudes. Thus, the hemispheric asymmetry of solar filaments at high latitudes in a cycle appears to have little connection with that at low latitudes. Our results support that the observed magnetic fields at high latitudes includes two components: one comes from the emergence of the magnetic fields from the solar interior and the other comes from the drift of the weak magnetic activity at low latitudes. 4. We present a case study of two successive filament eruptions at the southeast limb of the Sun observed by Solar Dynamics Observatory (SDO) on 2012 April 19. At the initial stage of the firs
学科主题天文学
语种中文
公开日期2016-05-03
页码114
源URL[http://ir.ynao.ac.cn/handle/114a53/6626]  
专题云南天文台_太阳物理研究组
推荐引用方式
GB/T 7714
孔德芳. 太阳暗条长期活动的统计特征研究[D]. 北京. 中国科学院研究生院(云南天文台). 2014.

入库方式: OAI收割

来源:云南天文台

浏览0
下载0
收藏0
其他版本

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。